1. Field of the Invention
The present invention relates to a portable radio communication apparatus including a housing, and in particular, relates to a portable radio communication apparatus provided with a boom portion and a part of housing operating as an antenna.
2. Description of the Related Art
Recently, portable radio communication apparatuses such as cellular phones have been increasingly made smaller in size and thinner. In addition, the portable radio communication apparatuses have been not only used as conventional cellular phones but also transformed to data terminal apparatuses for transmitting and receiving E-mails and for viewing web pages through WWW (World Wide Web). Due to this, liquid crystal displays have been made larger in size. In these circumstances, folding cellular phone terminals, which are considered to be suited to make the portable radio communication apparatuses smaller in size and make the liquid crystal displays larger in size, have been spread as disclosed in the following publications:
(a) Japanese Patent Laid-open Publication No. 2001-156898;
(b) Japanese Patent Laid-open Publication No. 2002-084355;
(c) Japanese Patent Laid-open Publication No. 2002-335180;
(d) Japanese Patent Laid-open Publication No. 2002-299931; and
(e) Japanese Patent Laid-open Publication No. 2002-516503.
However, since an external antenna protrudes from the upper housing, a user often feels uncomfortable as follows. When the user takes out the portable radio communication apparatus from his pocket, the external antenna is disadvantageously got stuck in his pocket. When the user sits on the chair with the communication apparatus put in his trouser pocket, the external antenna is uncomfortably and strongly pressed onto the user. On the other hand, when the communication apparatus is suspended from the user's neck without being put into his pocket, the center of gravity of the external antenna disadvantageously deviates from the center of the communication apparatus, and the external antenna disadvantageously becomes unbalanced because of its asymmetric structure in which the external antenna is located on either the right or left end portion of the portable radio communication apparatus.